Sugar in fruit

Thought I would share this from Harvard med.

Ask the doctors: How much fruit can I eat and stay within the sugar guidelines?

Q: I just read that we shouldn't be getting more than 10% of our calories from sugar. Should I cut back on fruit?

A: While it's a good idea to limit sugars from processed foods, you can worry less about eating too much fruit. In fact, one small study found no ill effects in people who ate 20 servings of fruit a day for 12 to 24 weeks.

Whole fruits are full of antioxidants and other nutrients and are high in fiber. Although fruits contain quite a bit of sugar, it is packaged inside cells, so digestive enzymes have to break down the cells to free fruit sugars, releasing them slowly into the bloodstream. When you eat an apple, you remain sated longer and are less likely to overeat than when you have a donut, whose sugar is immediately available.

Enjoy a variety of fruits, with one caution: stick to whole fruit instead of juice. The process of squeezing the fruit breaks open the cells, releasing the sugars. When you drink a glass of apple juice, you're going to get more sugar into your blood faster, and are likely to feel hungry sooner, than when you eat an apple.

— Hope Ricciotti, M.D., and Hye-Chun Hur, M.D., M.P.H., Editors in Chief, Harvard Women's Health Watch

10 Replies

  • One of my peeves regarding the various incarnations of the food pyramid, is that fruits & vegetables are treated as equals. We are advised to eat x "servings of fruits & vegetables" daily.

    Another peeve is that all fruits are treated as equals. This is not so in the diabetic world, however.

    There is nothing natural about modern fruits. Bitter, protective, polyphenols have been bred out of fruit & the sugar content has been amped up.

    Non-starchy vegetables "are full of antioxidants and other nutrients and are high in fiber" - without the sugar.

    Ask an informed person about the dangers of soft drinks & s/he might mention fructose in the first sentence. Ask that person what kind of sugar is found in fruit, & ...

    In fact, fruit contains a mix of sugars. Some are actually high in glucose. Goes right into the blood. Fructose is safe for diabetics. However, the way that fructose is metabolizes poses a problem for the body in quantity. Typically, safe fruits are those that end in "berry", & one would not make a meal of them.

    There are people who become fruitarians. Out of all of the extreme forms of diet, fruitarianism is the most ruinous to health.

    There is so much wrong with the tone & content of the cited article. e.g.:

    "When you eat an apple, you remain sated longer and are less likely to overeat than when you have a donut, whose sugar is immediately available."

    If I were to eat a sugar donut, I doubt that it would make me overeat. I can't think of anything more guaranteed to destroy an appetite. A traditional donut is deep-fried. Fat is part of the pleasure. Fat sates the appetite as effectively as the fiber in the apple.

    Sugar (sucrose) is a molecule of glucose bound to a molecule of fructose. The molecules are separated during digestion. The sugar is not "immediately available". Unlike glucose. Donuts contain sucrose - but so do many fruits.

    I feel that it's important to restore insulin sensitivity when we have PCa. I'm assuming that most of us have a degree of insulin resistance. Insulin is a PCa growth factor. The ratio triglycerides:HDL cholesterol is a surrogate for resistance (= over-production). Makes little sense to eat any fruit not recommended for diabetics.

    Fructose is beneficial in PCa in that it can extend production of the hormonal form of vitamin D. But there is a limit to the amount of fructose that the liver should have inflicted on it.


  • Sorry i posted it, should have consulted with you first. What do Harvard docs know anyways?

  • Thought I'd dip into the USDA database to show how fruits vary in sugar types. G=glucose, F=fructose, S=sucrose

    1] Banana: 5% G, 5% F, 2.5% S

    2] Cherries: 6.5% G, 5.5% F

    3] Cranberries: 3.5% G

    4] Mango: 2% G, 5% F, 7% S

    5] Honeydew: 2.5% G, 3% F, 2.5% S

    6] Oranges: 2% G, 2% F, 4.5% S

    7] Peaches: 2% G, 1.5% F, 5% S

    8] Pears: 2.5% G, 6.5% F, 0.5% S

    9] Pineapple: 1.5% G, 2% F, 6% S

    10] Plums: 5% G, 3% F, 1.5% S

    So glucose content varies from 1.5% to 6.5%, as does fructose, while sucrose ranges from zero to 7% in the above sample. Although, bear in mind that sucrose is 50% glucose & 50% fructose.

    Unlike most cancers, PCa does not prefer glucose for fuel. The danger of glucose is in the effect on insulin levels. From 2009:

    "Crude prostate cancer incidence was 154 prostate cancers per 100,000 person-years in the lowest quartile of fasting serum insulin vs 394 prostate cancers per 100,000 person-years in the highest quartile."

    "Elevated fasting levels of serum insulin (but not glucose) within the normal range appear to be associated with a higher risk of prostate cancer."

    From 2004, a study of dietary GI (glycemic index) & GL (glycemic load):

    "Compared to the lowest quintile of GI, the {risk factors} were 1.23, 1.24, 1.47 and 1.57 for subsequent levels of GI. The corresponding values for GL were 0.91, 1.00, 1.20 and 1.41. "

    Sugar (from any source) matters, as does a high-carb diet. Even complex carbs cause glucose spikes in the absence of fats.


  • I agree Patrick and I consume a total carbogram of 15 per meal and 10 at night snack (55 per day). 15 is about 1 and 1/2 slices of bread. This helps me control insulin intake. I always have around 15 per meal to avoid sugar lows. I also cut down on fat to about zero, no starchy fruits or veggies. I eat a lot of salads. Any other ideas?

  • Hate to inform you, but doctors in general get virtually no education in nutrition and healthy lifestyles. They are NOT experts, unless they have taken the time to educate themselves. They do not learn it in med school, unless things have changed radically in the last 10 yrs.

    Go to Dr Gabriel Cousens website if you want to learn about sugar and cancer and fruit.

  • About nutrition? Only what Big Pharma allows them to say.

  • I liked the article.

  • This is not too difficult to comprehend. Cane sugar, bad. Fruit sugars, good.

    My bro is a fragile diabetic, he can eat all the fruit he wants. The body renders different sugars in different ways. I learned that in grade school.


  • ......and I'm reading this just after I finished eating a chocolate chip cookie.

    I used to follow a mainly plant-based diet, sugar free as much as possible,

    no red meats, no dairy, some chicken, fish and eggs.

    The side effects from the meds and the cancer itself were causing me major weight loss, loss of appetite, and muscle mass. And my weight fell to 119 after I had an episode of the flu in Jan/Feb. 2015 which landed me in the hospital.

    So I asked my doctor about diet, and he smiled sadly at me and said, "Just eat whatever you want...." Food tastes like cardboard to me, for the most part, and I don't enjoy eating, but now I struggle to force myself to try to regain some weight and strength. I just went through twenty radiation treatments, which caused me a lot of fatigue, in addition to the fatigue I experience from the Xtandi.

    So now I try to eat foods which produce more energy and can help me to at least stop losing more weight---foods more densely-packed with nutrition.

    I don't believe that any particular diet could cure me---it might slow the progression, but in the long run I need to try to keep up my strength, first priority.


  • I've read that fruits are PC-fighters, & that we should eat a variety. Different nutrients in different colors of fruit. It's very important to eat organic fruit. If you have a problem with that, like access or cost, look up which fruits (& veggies, too) are best or worst to eat in nonorganic form. I'll always remember a friend's comment (on this topic) that strawberries are like little sponges.

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